Contact lenses intended for correcting myopia (nearsightedness) or hypermetropia (farsightedness) have a central optical zone that imparts a negative or positive spherical correction (also referred to as power correction) to the lens. Zones peripheral to the optical zone are mainly provided for fitting. The term "spherical contact lens" is often used to denote a contact lens intended for correcting myopia or hypermetropia having spherical or near-spherical surfaces, as distinguished from lenses having a toroidal surface that imparts a cylindrical correction to compensate for an astigmatism. However, as known in the art, even though spherical posterior and anterior surfaces provide acceptable visual acuity, spherical aberration may be introduced into the lens due to the geometry of the lenses. One manner used to compensate for spherical aberration has involved providing a lens surface with asphericity in an attempt to eliminate the spherical aberration.